Coupling device for high frequency apparatus



y 2, 1933- c. F. RUDOLPH 1,907,391

COUPLING DEVICE FOR HIGH FREQUENCY APPARATUS 1 Filed March 8, 1930 TT iwV IN V EN TOR. 80 81 10 5;: awofl li A TTORNE Y Patented May 2, 1933UNITED STATES CORRIE F. RUDOLPH, OF WASHINGTON, DISTRICT OF CGLUMBIACOUPLING DEVICE FOR HIGH FREQUENCY APPARATUS Application filed March 8,

My invention relates broadly to high frequency signaling apparatus andmore particularly to a flexible insulated coupling for the control ofmoving parts in high frequency telegraph apparatus.

One of the objects of my invention is to provide an improved insulatedflexible coupling construction for the rotative control of highfrequency signaling apparatus.

Another object of my inventlon is to provide a construction of insulatedjoint for a rotary shaft in a high frequency telegraph signalingapparatus.

A further object of my invention is to provide a construction ofinsulated coupling in which an insulated rod of high dielectric strengthis counterbored at each end thereof to receive portions of a controlledshaft and a controlling shaft with sufficient clearness to permit thenecessary vertical and hori, zontal alignment of the apparatus which iscontrolled with respect to the position of the controlling member.

Other and further objects of my invention reside in the construction ofinsulated coupling device as set forth more fully in the specificationhereinafter following by refer ence to the accompanying drawing, inwhich:

Figure 1 is a side elevational view illustrating the coupling device ofmy invention partially broken away and illustrated in cross-section withthe length thereof countershortened for purposes of illustration; Fig. 2is a plan view of the insulated coupling illustrated in Fig. 1; Fig. 3is a cross-sectional view through one of the connecting shafts whichextends into the counterbored portion of the insulated coupling; andFig. 4 is a, perspective view of the insulated coupling member of myinvention.

In high frequency signaling apparatus such as short wave radio telegraphtransmitters, a high degree of insulation is necessary to secure highefliciency of the operation in the apparatus. In mounting rotarymechanism in the transmitter, precaution must often be taken to insulatethe transmitting apparatus per se from the front panel structure of theapparatus. The adjusting shaft mechanism which operates the adjust-1930. Serial No. 134,283.

able inductance, capacity, or contact system in a short wave transmitteris insulated from the adjusting means according to my invention by ashaft member of isolantite or other insulation material having a highdielectric strength and serving as a good insulator with respect to highfrequency currents in'the transmitter circuits. An insulated shaft iscounterbored at oppositeends to receive the' ends of the controlledshaft and the controlling shaft, which shafts are locked with re-' spectto the insulated coupling by pin me1nbers which extend through thecounterbored portions of the shaft. Sufficient clearance is provided ineach end of the insulated coupling to permit the necessary vertical andhorizontal alignment of the controlled and controlling shafts.

The coupling construction of my invention will be more clearlyunderstood bydetailed reference to the drawing wherein referencecharacter 1 designates the insulator which is capable of outstandinghigh frequency voltages or fields. The insulator l is pref erablycircular in cross-section and is counterbored at 2 in each end thereof,the depth of the counterbored portion being selected in accordance withthe requirements to which the insulator may be placed, but usually thecoupling is constructed precisely the same on 80 each end thereof andthe depth of the counterbored portions 2 is the same on each end of thecoupling. I have illustrated the insulated frame 12 of the highfrequency signaling apparatus which may be, for example, the end supportfor an inductance, the turns of which are carried by the insulatedstruts 1 1. A hearing 15 is carried in frame 12 through which tubularmember 16 passes and within which there is mounted the rotary shaft 17provided with screw 18thereon which may control rotary mechanismactuating an adjusting mechanism for the short wave transmittingapparatus. The shaft 17 has an end portion 3 thereon which isdiametrically slotted as indicated at 3a. By reason of the counterboredportions 2 of the insulator 1, there is provided at each end oftheinsulator a shell-like wall let housing a I the ends of the controlledshaft 3and' the controlling shaft 4. The controlling shaft 4 is providedwith a diametrically extending slot 4a in the end thereof similar to theslot 360 in the shaft 3. The insulator l is diametrically apertured at 7and 8 through shell portions 1a at each end thereof. The apertures atone side of the insulated shaft are smooth walled. The apertures on theopposite side of the shaft are screw threaded as indicated at 766 and8a, enabling the pins 5 and 6 having screw threads 50: and 6a on theends thereof to pass through the smooth walled apertures and to engagethe screw threaded apertures in the wall 1a, thereby establishingdiametrical members across the sockets 2 into which the shafts 3 and imay interlock. The screws 5 and 6 are each provided with adjusting heads55 and 6b which fit flush with the cylindrical surface of memberl sothat the insulator is interlocked with the opposite directed shafts 8and 4 without portions of the insulator projecting beyond thecylindrical contour thereof. The controlling mechanism for effectingadjust ment of the shaft 17 is mounted upon panel 20 which carries theframe 21 in which shaft 22 is journaled, the shaft being connected withcrank 23 controlled by handle 2%. A bevel gear 25 is carriedby shaft 22and meshes with bevel gear 26 for driving the counter 27 indicating theadjiiistment of the rotary shaft mechanism by readings visible throughthe front of the pancl20. The pins 5 and 6 form a solid union betweenprojecting shafts 3 and l and the insulated coupling as the pins aresmooth and are turned to a snug fit in the diametrical slots in the endsof shafts 3 and I. This arrangement permits a universal action of thejoint with no back-lash which is very necessary for close calibration ofthe frequency adjusting apparatus of a transmitt r where inaccuracies inalignment of the controlled shaft and controlling shaft normally occur.

The isolantite insulator resembles porcelain and provides insulation ofhigh dielectric properties. Other forms of insulation may be used otherthan isolantite where such insulationis of high dielectric strength withrespect to high frequency currents.

While I have described my invention in certain preferred embodiments, Idesire that it be understood that modifications may be made and that nolimitations upon my invention are intended other than are imposed by thescope of the appended claims.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is as follows:

1. In high frequency signaling apparatus. a frame, a panel spaced fromsaid frame, a driven shaft rotatablymounted and projecting throughsaidframe towards said panel, a driving shaft rotatably mounted through saidpanel and extending towards said frame substantially in axial alignmentwith the driven shaft and spaced well away from the same, facing ends ofthe shafts being each formed with a diametrically extending slot openingthrough its end and sides, a solid insulator formed of material havinghigh dielectric strength extending between said shafts and havingaxially extendingsockets leading from its ends and loosely receiving theslotted end portions of said shafts to permit side play, the distancebetween the sockets being appreciably greater than the depth of thesockets to provide a good insulation between the shafts, opposed Wallportions of the sockets being formed with openings, and pins extendingtransversely through the sockets with their ends engaged in the openingsand their intermediate portions extending through the slots ofthe shaftsand frictionally engaging walls of the slots in spaced relation to theirinnerends.

2. In electrical apparatus, a frame, a driven shaft journalled in saidframe, a panel, a driving shaft extending through said panel andsupported thereby substantially in axial alignment with said drivenshaft, said shafts having diametrically extending openings from side toside near their opposing ends, a solid insulator formed of materialhaving high dielectric strength and provided with sockets receptive ofthe ends of said shafts,,pins extending transversely through saidsockets and firmly secured in the insulator. walls which surround saidsockets, means including a solid central portion of said insulator formaintaining a high degree of insulation between said shafts ends, andmeans including said pins and the closely fitting walls of said shaftopenings for rendering said insulator substantially a universal jointbetween said drivingand said driven shaft and for reducing back-lash toa minimum.

CORR-IE F. RUDOLPH.

